Rogers LS3/5a (BBC) Speaker Review

[MaxwellsEq]

BBC LS3/X type speakers are never main monitors, the LS5/X are the main monitors.

Due to the small, but acoustically treated volume of OB trucks, these were expected to be a few inches from the wall. They were physically close to the operators and so always nearfield.

In other words, a 40 year old, "B class" production tool designed for nearfield listening, close to wall boundaries in a relatively acoustically dead space.

 

[DSJR]

The Harbeth P3ESR response looks pretty similar. Clearly deliberate.

Stereophile Aug12 2010 review by JA:

Harbeth P3ESR loudspeaker

Everyone wants something different from a loudspeaker. Some people value midrange neutrality above all, while others will sacrifice some of that accuracy to get extended lows or a speaker that will play immensely loud with only a few watts of power. Some want stereo imaging that is sufficiently...

www.stereophile.com

View attachment 328427

Now take 3dB at least away from the 120Hz bump which should give you some idea of the proper bass response!!!

The P3ESR may have a lifted top, but it's so sweet toned and well integrated in this model - NO TINSEL and beautiful on brushed cymbals! The ESR's bass is also in a different league in terms of level availability* although the DSP integrated Nelson sub-stand is intended to take the bass down to 35Hz or so but it's only a very low-level solution as the main speaker is kept full range (leading their customers slowly by the hand into the twenty first century a step at a time).

The ESR alone can happily play this track if volume isn't silly high and if it's pushed, it simply 'flubs up' rather than 'cracks' if you see what I mean -

 

[tomtoo]

Its not terrible, just more than 10 times to expensive.

 

[Karl-Heinz Fink]

Was it really? If so, they would have had to spec exact dimensions of said rooms, distance from the wall, etc. Do such specs exist? If not, I say it is justification after a fact. Today, in those exact situations we use flat response speakers, ergo those assumptions were not sound.

No, that's not true in my opinion. Professional active monitors have settings for those effects when used on a console or the wall. But maybe the BBC had those specs internally, but why should they publish them? They designed a speaker and gave a license to build it for their own internal use. Why should they talk to anybody about it? Again, it was never intended to be a HiFi speaker.

Look at those settings of Neumann 120. They have both mid and low at a maximum of 6dB and you could calculate from the baffle size the starting point of the compensation. For full compensation, you take down both settings to the maximum of 6dB.

So think about the LS3/5 as a speaker with the mid/lows down at around 4dB and some boost around 120Hz. You can't switch a passive speaker in the same way, so you must decide what to do with it before starting the design. The LS3/5 was a studio monitor to be used at space-limited places.

 

[MaxwellsEq]

BBC LS3/X type speakers are never main monitors, the LS5/X are the main monitors.

Due to the small, but acoustically treated volume of OB trucks, these were expected to be a few inches from the wall. They were physically close to the operators and so always nearfield.

In other words, a 40 year old, "B class" production tool designed for nearfield listening, close to wall boundaries in a relatively acoustically dead space.

It is worth describing something to people here who have not had the opportunity to experience it: an Outside Broadcast van or a small production cubicle where the LS3/5A was used a lot is very acoustically dead, compared to even the best treated domestic listening room.

It's hard to describe how much deader it is than any domestic listening room.

 

[DavidMcRoy]

Karl-HeinzFink wrote, "The LS3/5 was a studio monitor to be used at space-limited places."

Exactly. You might say that the BBC designed a dramatically better "continuity speaker" than the Auratone and this is it. It somehow found its way into hifi salons, stories were told, and here we are.

 

[MaxwellsEq]

No, that's not true in my opinion. Professional active monitors have settings for those effects when used on a console or the wall. But maybe the BBC had those specs internally, but why should they publish them? They designed a speaker and gave a license to build it for their own internal use. Why should they talk to anybody about it? Again, it was never intended to be a HiFi speaker.

Look at those settings of Neumann 120. They have both mid and low at a maximum of 6dB and you could calculate from the baffle size the starting point of the compensation. For full compensation, you take down both settings to the maximum of 6dB.

So think about the LS3/5 as a speaker with the mid/lows down at around 4dB and some boost around 120Hz. You can't switch a passive speaker in the same way, so you must decide what to do with it before starting the design. The LS3/5 was a studio monitor to be used at space-limited places.

I think you are correct (and this is based on hearing hundreds of different LS3/5A speakers in many different, small, acoustically dead spaces).

 

[DSJR]

Obviously, I would look at the speakers with a different eye. I can tell you what I see:

Bottom end: the Q of the speaker is pretty high, so that's the bump at 100 Hz. I'm sure this was chosen to compensate for the fact that nothing was happening at the lower end. It uses the trick of your brain reconstructing the fundamentals from the harmonics. Or maybe they simply did not get more BL into the woofer (there was no Neodymium around). The cabinet is clearly too small for the woofer.

Midband 1: If you mount a driver that measures flat on a large baffle into a cabinet, you will get a 6dB loss of bottom end level, beginning in the midband region - it's often called the baffle step. It's up to the designer to decide if he wants to compensate for the baffle step (for placing the speaker in free space) or leave it in for a speaker that goes to a wall or is used in nearfield (you don't "see" the baffle step in close nearfield) or something in between. On LS3/5, it is obvious that they left the baffle step in, so the speaker must go on a wall or be used in the near field.

Midband 2: The peak at 1.2kHz might partly come from the baffle step, but in this case, it's clearly more of a problem with the KEF woofer. It's the typical first-mode problem due to the "wrong" termination of the cone with the surround. Don't forget this driver was made before PP without help from modern FEA/BEA analysis programs. Later, KEF made an improved version with a high-damping surround (Rubber/ PVC compound) that measured better but had a lot of hysteresis and sounded awful. In the end, the old driver was used again. Unfortunately, this peak is inconsistent and changes from woofer to woofer.....a well-known effect of KEF B110. The distortion in the mid band goes together with this problem.

So, from a designer's point of view, I can see the idea of the monitor when it was made.
I like it from the historical point of view, but I never understood why so many companies started to introduce it again.....but that's another story.

Sorry to go on about these things here, but I knew one of the original makers well back then and he was also one of the original design team, albeit not one of the major players - you know him I believe K-H F ).

The bass bump was DELIBERATELY put there to try to make the sound at least less thin toned as say, the same size and driver Linn Kan was (even more ghastly to me as they almost clank as well as squeak on natural timbres), listening to music for pleasure or true accuracy was also NOT a goal here as OB van engineers needed to hear distortion and noise/hiss in the program and that really does explain the non-flat response.

Please give the BBC design team some leeway here, as they knew EXACTLY what this speaker was/is doing and it fitted its purpose very well in those old analogue days, something the Dynaudio BM5 seems to do today for them, at least in their compromised recently built glass walled broadcast rooms..

 

[dzerig]

For it's use as a monitor for radio stations, I think it's just fine, with the elevated treble to give more insight into details. Accuracy does not matter for this purpose.

From another review:

It should be noted by all potential collectors that these speakers have been engineered and crafted for use in a small, enclosed room.
The original design focused on the ability to produce the speakers repeatedly with identical performance. This neccessity was due to the professional usage of the LS3/5a. The goal was conclusively not to achieve unmet fidelity, but to produce a speaker series with consistent performance.

 

[Galliardist]

No need to criticise the BBC engineers of the 1960s, but whoever there thought it was OK to grant a licence and endorse selling copies of this speaker for audiophile use today should be rewarded with a big glass windowed executive corner office at the new office building in Salford.

.., and made to listen to Mahler sympathies on a pair of them for four hours a day until they stop it.

 

[Sokel]

I always wonder why KEF doesn't make a "historical" remake of this.
It could be good money (even for nostalgia reasons) for them and they surely know how as the original woofer manufacturer.

They could even collaborate with Focal in a truly historical "reunion" .

 

[Sokel]

.., and made to listen to Mahler sympathies on a pair of them for four hours a day until they stop it.

That's dark,no living thing deserves such fate.

 

[uwotm8]

A good friend of mine has a pair, which we listened to when he first got them a year or two ago. They are not remotely flat

Fun thing is, in room they're way flatter than some other "flat" speakers.
The more I listen to different speakers the more I think that most of the people (and me ofc) actually like room-engaged bass response.
We just fool ourselves thinking that we prefer "flat" response because it's not flat in room

 

[AudioSceptic]

This is a review, listening tests and detailed measurements of a vintage Rogers L3/5a monitor implementation licensed from BBC with the same name. It is on kind load from a member. New, it costs US $4895 a pair.
View attachment 328359
From the outside, there is nothing to distinguish this speaker from cheap bookshelves sold when it was manufactured. Back panel reveals no secrets either:
View attachment 328360

Owner kindly gave permission to leave the serial number on the picture for those of you who want to trace its lineage. Owner says it was manufactured between 1980 and 1987.

Searching for measurements, there are a few but are either old and crude, or have issues (e.g. stereophile measurements with incorrect bass response). So this test may be the first true measurement of this speaker.

Rogers LS3/5a Speaker Measurement
The grill can be removed but it wasn't easy to pull off so I tested with it on. From some reading I have done, speaker was designed with it being on to get rid of edge diffraction and such. Let's see the anechoic measurement:
View attachment 328361
Well, that is no good. Bass response is clearly wrong. It is uneven and low in level. We also have a pronounced resonance which one manufacturers of these clones claimed was due to age. I have seen the same in just about every measurement of this speaker so that doesn't sound right. It seems like "bog standard" woofer resonance due to it being used outside of its linear range:

View attachment 328362

Early window and predicted in-room response predictably don't look nice:

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Owner didn't want me to stress the speaker and asked for distortion at 76 and 86 instead of my normal 86/96 dBSPL @ 1 meter:
View attachment 328365
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The peak in distortion around 1.5 KHz is another reason to have crossed over the woofer earlier although it is unknown if the tweeter could handle that better.

Directivity is quite rough in horizontal axis:
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Vertically you better point the tweeter at your ear:
View attachment 328369

Waterfall shows clear resonance:
View attachment 328370

Step response shows an odd discontinuity in the woofer response which may be due to that resonance:
View attachment 328371

Edit: forgot the impedance plot:

View attachment 328375
Rogers LS3/5a Speaker Listening Test and EQ
Due to low bass output, overall sensitivity is quite low requiring cranking up the amplifier volume. Once there, my first female track didn't sound awful but was rather bright and somewhat rough. Filling in the bass hole completed the tonal range for vocals proving efficacy of our measurement. I then corrected a few other issues and fine tuned to get this:
View attachment 328372
Not only was the speaker much more balanced sounding, it also had more clarity. Those resonances were sure hiding detail and ambiance in the music. That last notch filter at 5 kHz was barely audible but the rest were much needed.

Once there, I was impressed with the volume this little speaker could produce and the large halo of sound it created in may admittedly very large space. I could imagine listening to two of them would have been more satisfying.

Conclusions
Much of what I read from companies who have cloned the BBC LS3/5a is around replicating components. Measurements seem to be an afterthought. That is the wrong way to do this as I could care less what components are used. If you want to replicate the old speaker, replicate its audible frequency response. That, is what we listen to, not what the parts do.

Now, it is possible the old BBC had the problems we see here in which case, why reproduce a faulty product and charge so much for it? It makes no sense to me. Get a proper speaker if your goal is enjoyment of music. The history is not going to pay the bills there.

I can't recommend the Rogers LS3/5a speaker/monitor. If you have it, a bit of filtering does it a lot of good, bringing the sound into hi-fi category.

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One of the ones I've been waiting for. What a disappointment! I've never owned any but had the impression they were pretty flat above 100 Hz and lacked only bass and power, making them surprisingly close to the original Quad ESL. Many companies had licences to build these over the decades and I wonder how much they varied?

 

[Willem]

I always wonder why KEF doesn't make a "historical" remake of this.

They did for while, but really all these modern copies are copies of an outdated design. As far as I know the Harbeth P3ESR is the only one that really advanced significantly on the original design, whether you like it or not. One aspect in which it is far superior is in subwoofer integration. The bass bump in the LS3/5a made it hard to integrate a subwoofer. The little Harbeth does not have such a bump, and hence benefits enormously from a subwoofer (I tried it just for fun).

 

[Willem]

And to remind people about their frequency response, it pays to actually read the original report that I linked to earlier, to see what the response was like originally, and measured in the BBC anechoic room rather than using modern approximations in the absence of a proper anechoic room (sadly the BBC since demolished their almost legendary anechoic room).

 

[MaxwellsEq]

No need to criticise the BBC engineers of the 1960s, but whoever there thought it was OK to grant a licence and endorse selling copies of this speaker for audiophile use today should be rewarded with a big glass windowed executive corner office at the new office building in Salford.

.., and made to listen to Mahler sympathies on a pair of them for four hours a day until they stop it.

The BBC licensed the manufacturers to make speakers for them. The licenses would not have restricted the vendors from selling them commercially. I suspect (given the date) that there was no money back to the BBC for people buying them commercially. BUT, the BBC would not have granted a license for public audiophile consumption - it wouldn't be in their gift.

 

[DanielT]

Thanks for the test Amir.

In a way, interesting test results, but the most interesting thing to read is you who tell us about the history, the purpose of these classic speakers.

 

[AudioSceptic]

You know that now that we know that you have a pair, we will hound you into sending one to Amir for testing. It is your duty for science.

You do know that these are not Spendor's version of the same speaker? They are a similar size but a different design, much as was Harbeth's P3.

 

[FrantzM]

Hi

Read @amirm review and some posts, not all mind you. This is a case of people taking a product and using it for the wrong purpose. If you were to read some of the HEA magazines, this LS3/5A was the bee knee of small speakers, a reference, perhaps , The reference.
It wasn't. It is not.
This review confirms what many who have heard this (I, included) suspected: The LS3/5A wasn't good as an audiophile or music lover speaker, in a home environment. As such it is not worth the large sum people (had to) pay for this and its clones/licensees/similars...

Again , Thanks @amirm .. One more veil lifted

Peace.